Coupling devices for hydraulically and mechanically coupling a fuel injector to a fuel rail are in widespread use, in particular for internal combustion engines. Fuel can be supplied to an internal combustion engine by the fuel injector assembly. The fuel injector assembly has fuel injectors that can be coupled to fuel injector cups in different manners.
In order to keep pressure fluctuations during the operation of the internal combustion engine at a very low level, internal combustion engines are supplied with a fuel accumulator to which the fuel injectors are connected and which has a relatively large volume. Such a fuel accumulator is often referred to as a common rail.
Fuel rails can comprise a hollow body with recesses in form of fuel injector cups. The fuel injector cups may also be hydraulically coupled to the fuel rail via pipe elements. The fuel injectors are attached to the fuel injector cups. The connection of the fuel injectors to the fuel injector cups that supply the fuel from a fuel tank via a low or high-pressure fuel pump needs to be very precise to get a correct injection angle and a sealing of the fuel.